Won't go into ready mode

2005 Prius
The car will not go into ready mode. It failed while I was working delivering packages. I had to switch cars and tow this one back after work.
Codes are C2310 and C2318
12V battery is not great, but a jumper battery doesn't help.
I have replaced the HV battery and tried charging the HV battery before reinstalling.
I will buy a new 12V battery today, but I hold little hope for it.